 Login 
IOS-XR and Nexus: EBGP peering example with different AS per-router
12.02 2024 | by massimilianoarchitettura di riferimento NEXUS-R3 configuration router bgp 65514 vrf EXAMPLE address-family ipv4 unicast redistribute direct route-map CONNECTED neighbor 10.255.255.1 description […]
architettura di riferimento
NEXUS-R3 configuration
router bgp 65514
vrf EXAMPLE
address-family ipv4 unicast
redistribute direct route-map CONNECTED
neighbor 10.255.255.1
description to_R1
remote-as 65512
timers 10 30
password <password>
address-family ipv4 unicast
disable-peer-as-check
route-map Weight-Out out
maximum-prefix 10000 50 warning-only
soft-reconfiguration inbound
neighbor 10.255.255.2
description to_R2
remote-as 65513
timers 10 30
password <password>
address-family ipv4 unicast
disable-peer-as-check
maximum-prefix 10000 50 warning-only
soft-reconfiguration inbound
neighbor 10.255.255.4
desciption to-R4
remote-as 65515
password <password>
update-source vlan 10
address-family ipv4 unicast
next-hop self
!
interface Vlan100
ip address 10.0.0.1/8
!
route-map CONNECTED permit 10
match ip address prefix-list DIRECT
route-map Weight-Out permit 10
set weight 200
!
ip prefix-list DIRECT 10.0.0.0/8
NEXUS R4 configuration
router bgp 65515
vrf EXAMPLE
address-family ipv4 unicast
redistribute direct route-map CONNECTED
neighbor 10.255.255.1
description to_R1
remote-as 65512
timers 10 30
password <password>
address-family ipv4 unicast
disable-peer-as-check
route-map Weight-Out out
maximum-prefix 10000 50 warning-only
soft-reconfiguration inbound
neighbor 10.255.255.2
description to_R2
remote-as 65513
timers 10 30
password <password>
address-family ipv4 unicast
disable-peer-as-check
maximum-prefix 10000 50 warning-only
soft-reconfiguration inbound
neighbor 10.255.255.3
desciption to-R3
remote-as 65514
password <password>
update-source vlan 10
address-family ipv4 unicast
next-hop self
!
interface Vlan100
ip address 10.0.0.1/8
!
route-map CONNECTED permit 10
match ip address prefix-list DIRECT
route-map Weight-Out permit 10
set weight 200
!
ip prefix-list DIRECT 10.0.0.0/8
IOS-XR R1 configuration
router bgp 65512
vrf EXAMPLE
address-family ipv4 unicast
neighbor 172.16.1.1
remote-as 100
timers 10 30
descripion to-PEA
password encrypted <password>
ttl-security
address-family ipv4 unicast
route-policy EXAMPLE-IN in
route-policy PASS_ALL out
maximum-prefix 10000 50 warning-only
neighbor 10.255.255.3
remote-as 65514
timers 10 30
description to-NEXUS-R3
password encrypted <password>
address-family ipv4 unicast
route-policy PASS_ALL in
route-policy PASS_ALL out
maximum-prefix 10000 50 warning-only
soft-reconfiguration inbound
neighbor 10.255.255.4
remote-as 65515
timers 10 30
description to-NEXUS-R4
password encrypted <password>
address-family ipv4 unicast
route-policy PASS_ALL in
route-policy PASS_ALL out
maximum-prefix 10000 50 warning-only
soft-reconfiguration inbound
!
route-policy EXAMPLE-IN
if as-path in AS_EXAMPLE_PERMIT then
pass
elseif (destination in PFX_Example_Permit_IN) then
pass
endif
end-policy
!
as-path-set AS_EXAMPLE_PERMIT
#DCRM
ios-regex ‘_400$’,
#DCMI
ios-regex ‘_500$’
end-set
prefix-set PFX_Example_Permit_IN
10.0.0.0/8
end-set
IOS-XR R2 configuration
router bgp 65513
vrf EXAMPLE
address-family ipv4 unicast
neighbor 172.16.1.2
remote-as 200
timers 10 30
descripion to-PEB
password encrypted <password>
ttl-security
address-family ipv4 unicast
route-policy EXAMPLE-IN in
route-policy EXAMPLE_OUT out
maximum-prefix 10000 50 warning-only
neighbor 10.255.255.3
remote-as 65514
timers 10 30
description to-NEXUS-R3
password encrypted <password>
address-family ipv4 unicast
route-policy PASS_ALL in
route-policy PASS_ALL out
maximum-prefix 10000 50 warning-only
soft-reconfiguration inbound
neighbor 10.255.255.4
remote-as 65515
timers 10 30
description to-NEXUS-R4
password encrypted <password>
address-family ipv4 unicast
route-policy PASS_ALL in
route-policy PASS_ALL out
maximum-prefix 10000 50 warning-only
soft-reconfiguration inbound
!
route-policy EXAMPLE-IN
if as-path in AS_EXAMPLE_PERMIT then
pass
elseif (destination in PFX_Example_Permit_IN) then
pass
endif
end-policy
!
as-path-set AS_EXAMPLE_PERMIT
#DCRM
ios-regex ‘_400$’,
#DCMI
ios-regex ‘_500$’
end-set
!
route-policy EXAMPLE-OUT
set med 200
end-policy
!
prefix-set PFX_Example_Permit_IN
10.0.0.0/8
end-set